Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography ISSN 1598-4850(Print) Vol. 35, No. 4, 281-290, 2017 ISSN 2288-260X(Online) https://doi.org/10.7848/ksgpc.2017.35.4.281 Original article

GIS-based Preliminary Feasibility Study for the Optimal Route Selection for - Railway through

Acharya, Tri Dev1)·Yang, In Tae2)·Lee, Dong Ha3)

Abstract Transportation plays a vital role in sustainable development, and moreover, bulk transportation provides cost effective movement of goods and human beings with less environmental issues. Nepal is a developing country with increasing urbanization and transportation demands. The growing interest of China to connect with Southeast Asia through Nepal has led to ambitious project proposal of Rasuwa Gadhi to Railways, which is the shortest route from China to India. Lack of updated geospatial data has lead the concerned authorities in Nepal to be dependent on analysis and proposals from donor nations. Taking such considerations, based on GIS and free data, this study explores optimal routes to connect cites using slope and land cover. Based on reclassified slope, two shortest optimal routes were found. One passing through Baireni in Dhading and another through towards Birgunj with length of around 172 Kilometers. The study shows that available open source data can be used of preliminary feasibility studies and yet shows limitations for detailed economy based planning. Development and use of high resolution updated geospatial data is of high necessity for Nepal to become self-sustained in planning of development works.

Keywords : GIS, Optimal Route, Least Cost Path, Rasuwa Gadhi, Birgunj, Railway, Nepal

1. Introduction Hills and in North and the rest is lowlands in the South. Here two wheeler motorbikes are very common Transportation plays an important role in the modern means of personal transportation whereas van, microbuses world. Effective transportation network is a basic need for and buses are common for inter and intra-city transportation. sustainable development that helps to carry goods as well as With gradual increase in population in the capital, the long helps us to commute from one place to another in a short distance commute and transfer of goods has been much period of time via land, water and airways. High speed demanding. Using small vehicles for this purpose leads to bulk transportation such as railways redefines the standard traffic congestion as well as environmental issues (Yang et in terms of distance and journey time. They strengthen al., 2014). Hence, railways can be very crucial means of bulk national economy and help in environmental issues. In many transport for Nepal to connect both neighboring countries developed countries, railways have changed commuters’ as well as meet the demand of such growing population and habits in large cities. development. Currently, Nepal has 53 Kms (Kilometers) Geographically, Nepal is a landlocked country bounded of rail track, out of which the narrow gauge trains are between China and India which has more than 80% of operational only in the 32 Kms -Jayanagar route

Received 2017. 07. 31, Revised 2017. 08. 15, Accepted 2017. 08. 31 1) Member, Dept. of Civil Engineering, Kangwon National Univ., Korea (E-mail: [email protected]) 2) Member, Dept. of Civil Engineering, Kangwon National Univ., Korea (E-mail: [email protected]) 3) Corresponding Author, Member, Dept. of Civil Engineering, Kangwon National Univ., Korea (E-mail: [email protected])

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

281 Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography, Vol. 35, No. 4, 281-290, 2017 in flatlands of . With the intent of providing the bulk to Purang (Burang), near the tri-junction Nepal--India railway transportation, DoR () has and Yatung (Yadong) in the Chumbi Valley adjacent to forwarded the proposal for the construction of MM (Mechi- Sikkim (Fig. 1). It is an important route in OBOR (One Belt Mahakali), KP (Kathmandu-) and KB (Kathmandu- One Road) initiative, which is an ambitious plan of China Birgunj), KR (Kathmandu- Rasuwa Gadhi) Electric Railway to connect its western region to Asia, Europe and African Line (Acharya et al., 2017). Among these, feasibility study on regions through air, water and land ways. As per the request MM and KP has already been completed whereas proposals from Nepal, China has already agreed upon to investment has been called for KB and KR. The government has kept and to extend support in mega projects in Nepal, which will the construction of the MM Railway in high priority and as boost economic, cultural and religious communication. For national pride considering the inevitability of the reliable this, Chinese government has announced plans to extend the development of roadway and railway for attaining long-term Qinghai-Tibet Railway to Rasuwa Gadhi in Nepal through socio-economic prosperity in the country. the Shigatse-Kyirong stretch by 2020. Rasuwagadi can be an entry of Chinese market to Southeast Asia. The line is significant as transportation for passenger and freight trains will be cheaper, secured, less time consuming and environment friendly. Although these are very ambitious and expensive projects, it will pay in long run. New routes that are proposed, should be made such that they satisfy the constructions possibility, cost and current as well as future demands. Effective route selection process is very important for minimizing the cost. In planning a suitable road network, planners put into consideration factors Fig. 1. Routes for Qinghai railways to Indian and Nepalese like gradients or slope of the area, available land-use and soil border in Tibet (Jia and Liqiang, 2016) type, community or national landmarks and governmental China has shown a continuous interest in linking itself to interest. This is where technologies such as GIS (Geographic Southeast Asia through roads and bridges in Nepal. China Information System) help in greater deal. GIS is a system has already built necessary infrastructures on its side at of storing, retrieving and presenting both spatial and non- Kyirong. Blacktopped road up to the Nepal border from its spatial data in an efficient, quick, and structured way. It is national highway linking Tingri, Lhatse and Shigatse has considered as an important and useful tool in the field of already been constructed. Huge investment has been done transportation engineering and providing the capability to build necessary infrastructures to open the Rasuwa to perform transportation analyses. In design process, Gadhi-Kyirong border point for international trade along GIS helps minimize the impact on environment by proper both sides, such as construction of customs office, roads and selection of route, a critical first step in the process of design bridges linking both sides and renovation to improve roads and construction, which has a significant potential to impact on Nepalese side. With the Tatopani-Khasa route remaining the construction and environmental aspects of the area. closed since the massive earthquakes of 2015, traders have Based on the input conditions, GIS has been used in many been using Rashuwagadi-Kyirong route for trade with China multi-criteria geospatial decision support systems to solve leading to proper establishment of immigration offices on various problems in transportation such as suitable route both sides. Apart from the roadways, railways has been a construction, fast traffic routing, safe driving path selection big priority for Chinese government and a very necessity to etc. (Effat and Hassan, 2013; Stefanakis and Kavouras, 1995). Nepalese side. China wants to build three extensions to the Among the available GIS-based techniques, LCP (Least Cost Qinghai-Tibet Railway by 2030 and continuing its journey Path) is particularly useful to this purpose. Many researchers

282 GIS-based Preliminary Feasibility Study for the Optimal Route Selection for China-India Railway through Nepal have used LCP analysis, which allows them to find the 2. Study Area “cheapest” way to connect two locations within a cost surface that can be computed by combining multiple criteria, and The study area was selected based on the most feasible and therefore by accounting for different issues (environmental shortest route between China and India through Kathmandu, impact, economic investment, etc.) (Collischonn and Pilar, the capital of Nepal. The proposed mega projects for railways 2000; Douglas, 1994). Usually, geotechnical, geometrical, in Nepal will be connecting Kathmandu to Chinese border social and economic factors are used for the multi-criteria in two ports Rasuwa Gadhi and , Indian border in evaluation in selecting route (Farkas, 2009). Birgunj, major city Pokhara and a Buddhist pilgrimage site, Despite the fact that Nepal can provide the shortest land . The current situation of transportation link in the route between the two economic giants of the world, Nepal area is using Roadways as shown in Fig. 2. lack the transportation infrastructures to rip the benefits due In order to connect China to India, Kodari to Birgunj is to its difficult geography and poor economy. Currently, the the shortest and widely used main trade route before massive 265 Kms long road linking Rasuwa-Trishuli- is the earthquake. But after series of disasters such as massive shortest land route between China and India and is very risky landslide on August, 2014 (Acharya et al., 2016) and massive to travel. The developing nation could not itself construct the earthquake on April, 2015 in Araniko Highway (Kodari infrastructure and rather depends on foreign aids. One of the to Kathmandu), the route needs extensive reconstruction main reason is lack of updated geospatial data. The latest (Yang et al., 2016). And a recent damage of Phulping available topographic maps were developed in three phases: Bridge at Larcha has cut off the only connection to Tibet 1996, 1999 and 2001. And these maps were created by then in Araniko Highway. Hence, Rasuwa Gadhi was opened as His Majesty’s Government of Nepal through interpretation of an alternative gateway and has been given high priority by 1992 aerial photographs with the help of Finnish Government. both the governments. Infrastructures are being built on both Since then, very few updates were done in main cities such sides of border with the possibility of the border point being as Kathmandu or special interest from donors such as JICA connected with Chinese railways. Birgunj is a major trading for Lumbini. In such case, the developing nation’s government point for Nepal as over 70 percent of its import and export are cannot assess the pros and cons of a mega project such as done through the border entry point. Hence, we selected the railway roads for Nepal. This is where open source data area between Rasuwa Gadi and Birgunj for the optimal route plays a very crucial role for developing countries. There are selection for railway. multiple available geospatial datasets such as administrative boundaries, satellite imageries, elevation, land cover, drainage etc. These datasets are increasing in number with the updating geospatial technologies. Developing nations can better analyze the issues and propose best alternatives for development works by implementing simple geospatial tools on these datasets rather than completely dependent on foreign proposals. In this study, we used the freely available DEM (Digital Elevation Model) and Land cover dataset to derive various routes for railway alignments between Rasuwa Gadhi and Birgunj using LCP analysis over the cost of slope and land cover. Among the various cases, optimal routes were selected after comparison based on distance and connecting cities. The Fig. 2. Study area along with DEM (Digital Elevation study shows the importance of open source data that could be Model) and current road network connecting Kathmandu very useful for preliminary studies for developing countries. with border and major cities

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A rectangular area covering both borders from North to factor that determines the load to the locomotive and South in Nepal is considered as study area. It extends between is useful in determining speed, bents and loads while in 26°55'21.77" - 28°20'49.09"N latitude and 84°48'33.72" - operation. Hence, lower slopes 0-3 % which were standard 85°33'27.49"E longitude. The area covers high hills to flat for the railway gradient were given lowest cost value and plains with valleys and river ways. Land cover is mostly gradually increased till 15% and more as shown in Table 1. dominated by forest in north and flat agriculture land in 2. Distance to rivers: Rivers were derived from the void south with few concentrated cities along the highway routes. filled DEM so that the nearby areas can be avoided to prevent future disasters such as landslides and flood etc. 3. Data Used 3. Distance to ridges: Ridges are the peaks of the hills in which the construction is not very suitable and would Two major dataset were used for the study. Both dataset are require more effort in moving excavated materials and available freely in the web for download. taking construction materials. Also, the risk of damage A. DEM (Digital Elevation Model): SRTM (Shuttle Radar in case of railway cars falling from high ridges could be Topography Mission) DEM version 3 (Slater et al., 2006) high in future. was extracted from the OpenTopography portal. SRTM B. Land cover map: A 30 meter resolution national land cover obtained near global most complete high resolution database of Nepal (Uddin et al., 2015) derived using the digital topographic database of Earth. SRTM consisted Landsat imagery was downloaded from RDS (Regional of a specially modified radar system that flew onboard Database System) portal of ICIMOD (International Centre the Space Shuttle Endeavour during an 11-day mission in for Integrated Mountain Development). It was the first February of 2000. Version 3 eliminated the voids in the and most complete national land cover database of Nepal NASA SRTM DEM by filling the voids with elevation prepared using public domain Landsat TM data of 2010 and data primarily from the ASTER GDEM2 (Global Digital replicable methodology. The study showed that nearly 39.1% Elevation Model Version 2) and secondarily from the and 29.3% of Nepal is covered by forests and agriculture USGS GMTED2010 elevation model or the USGS National whereas the rest were bare lands, glacier, water and built-up Elevation Dataset (NASA JPL, 2013). The downloaded urban areas (Uddin et al., 2015). Grassland and shrub land DEM was filled and then used to derive inputs for the cost were given the least cost value compared to cropland and surfaces for the route selection. hilly forests. The rivers and barren lands on both sides of 1. Slope: As slope gives the idea of how much the surface is bank were given high cost value due to the high construction inclined to the horizontal, it provides basic idea of the cut cost of the bridges. Similarly, land acquisition in cities is fill estimation for the construction. Also, it is the major very expensive, so it was also given high cost value.

Fig. 3. Inputs factors used in the study (a) Slope, (b) Land cover, (c) Distance to river, and (d) Distance to ridges

284 GIS-based Preliminary Feasibility Study for the Optimal Route Selection for China-India Railway through Nepal

4. Methodology The reclassified layers were weighted overlaid in order to drive the four types of cost surfaces: A, B, C and D were The general workflow of this study is shown in Fig. 4. After derived as shown in the Table 2 weights. The case A only uses deriving the input datasets for the optimal route selection slope, the case B uses categorical reclassified slope. The third for China-India Railway through Nepal, these dataset were case C uses weighted slope as well as land covers, whereas reclassified into classes representing the cost value (1 being the fourth D condition takes consideration of distance to river lowest and 5 being highest cost) for suitable routing, which is and ridges. shown in Table 1. Table 2. Weighted overlay of different cases of cost surface used in the study

Case Dataset Weight (%) A Unclassified Slope 100 B Reclassified Slope 100 Reclassified Slope 80 C Land cover 20 Reclassified Slope 60 Land cover 20 D Distance to river 10 Distance to ridge 10

Cost distance analysis was performed on each of the Fig. 4. Workflow adopted in the study cost surfaces for a destination point. The value of each cell represents the cost per unit distance of crossing that cell, Table 1. Cost value for reclassified class or the input (which does not include the physical distance travelled as dataset a measurement). Similarly, cost direction surfaces were Dataset Class Cost Value developed which connects the destination for the direction 0-3 1 purpose. And finally, the least cost analysis was performed 3-5 2 such that the cost as well as movement is minimum. Slope 5-10 3 For each of the cost surfaces, the routes connecting Birgunj 10-15 4 directly to Rasuwa Gadhi and sub-routes connecting two 15< 5 major cities Baireni in Dhaging district and Kathmandu were also developed to see the more detailed variation in the route. Distance to 0-100 2 river 100< 1 5. Results and Discussion Distance to 0-100 2 ridge 100< 1 First of all, the destination cities to be connected for the Grass land, Shrub land 1 routes were identified. In this study, Rasuwa Gadhi customs Agriculture land 2 port in China and Birgunj customs port in India are destination Needle/broad leaved Land cover open/close forest 3 and origin stations respectively. Since, current roadway from Built up area 4 Rasuwa Gadhi ends at Baireni to connect Prithivi Highway and in future China will extend railway to Lumbini in Bare land, River, Lake, 5 Snow/glacier future, Baireni was also selected as an intermediate station.

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Also assuming the need of transportation in the capital city, and could lead to much drastic difference in route. Hence, Kathmandu has been also selected as an intermediate station. a reclassified categorical cost was developed as shown in Now the four cost rasters were prepared based on the cost Fig. 5(a). Fig. 5(b and c) shows the reclassified cost surfaces distance of Rasuwa Gadhi as destination and other stations that uses reclassified slope, land cover, distance to river and as origin. Fig. 3(a) shows the cost value strictly based on ridges as per the Tables 1 and 2. In Fig. 5 the valley and the slope without any categorization of class. The slope based south flat plains as well as some river valleys are shown to cost considers that the lower sloped terrain is best for the have low cost surface. And the rest has hilly forest with high construction as well as transportation as trains needs much raster cost which would increase the cost of construction of smooth flat rail tracks. But, as the ideal case of 0-3% slope is route. From the interpretation of the cost raster also, once can good for railroads, it was categorized into a least cost. This see that the route can be passed through river valleys and can is because in south flat plains 0-3% is a very sensitive terrain be joined straight in the plains.

Fig. 5. Results of cost surfaces (a) Reclassified Slope (case B), (b) Reclassified Slope and Land cover (case C) and (c) Reclassified slope, land cover, distance from river and ridges (case D)

Fig. 6. Results of least cost routes from Birgunj to Rasuwa Gadhi (a) Direct cases over DEM, (b) Inter-city cases and (c) Optimal case over satellite scene

286 GIS-based Preliminary Feasibility Study for the Optimal Route Selection for China-India Railway through Nepal

After running the LCP for each scenario, it resulted into also shows almost same distance. From these multiple four alternative routes based on Table 2 cases i.e. slope, cases and all connecting routes among cites, two optimal reclassified slope, reclassified slope and land cover and paths were selected as shown in Fig. 6(c). The route choice reclassified slope, land cover and distance to river and ridges depends on whether the railway shall pass through Baireni (Fig. 6(a)). For better comparison of the alternative routes, or Kathmandu. Passing through is two connecting stations Baireni and Kathmandu were used much better choice as most import from China and India is as alternative routes for each case as shown in Fig. 6(b) consumed in Kathmandu and can lead to cheaper means for and Table 3. Among the results, direct route, and route via the capital city. As government has planned for the KB and Kathmandu as well as Baireni shows the least distance KR railway, route passing through Kathmandu is a better among the other alternatives. Among all the cases, purely alternative. At the same time, acquisition of lands in the slope based case produced the longest distance. As stated valley could be much costly as well as difficult to negotiate earlier, it takes large distance to have a change in the slope with locals. If the route as shown in Fig. 6(c) is adopted, Bidur in south flat plains, routes in case A resulted in much longer municipality can be a connecting station. It could be a transit and were not very reasonable. Cases B, C and D shows much station that links towards Kathmandu in East and connects better results compared to case A. Even though, case D Baireni in the West and later towards Pokhara or Lumbini in showed shortest distance, the generalization in the land cover western Nepal. The result is much similar with the proposed has lead the route through hilly forest, which could increase ones by the Chinese companies in mid-2016 while submitted the cost of cut/fill. The best result is shown by case B which a feasibility report for a rail link between Kathmandu and used reclassified slope and followed uniform gradient across Pokhara (Humagain and Giri, 2016). In their proposal, the river valley passing to the capital city and getting out to Baireni was selected as it could connect Pokhara as well as south plains. Due to low resolution dataset, the routes were later can be connected to Lumbini with Kurintar as well. not very suitable for estimating the crossings over river and The use of freely available open source data not only be rivulets for bridge construction estimations. able to evaluate the feasibility of the proposed routes and In case of individual intercity connections, the routes are stations from the Nepalese perspectives such as future cities, much similar to the direct connection which passes through current transportation demand, energy efficiency etc. but also Kathmandu. Similarly, the route passing through Baireni limit the dependency from foreign companies. But, in order

Table 3. Results of length in kilometers of least cost routes of different cases from the study

Distance in Kilometers Route Via Sub-routes Case A Case B Case C Case D - Rasuwa Gadhi - Birgunj 347.55 205.21 184.11 172.03 Rasuwa Gadhi -Kathmandu 117.82 95.61 88.55 68.51 Kathmandu Kathmandu - Birgunj 245.89 111.55 108.36 103.73 Sum 363.71 207.16 196.91 172.23 Rasuwa Gadhi -Baireni 82.74 80.20 79.42 74.28 Rasuwa Gadhi - Baireni Baireni - Birgunj 163.80 136.31 101.79 97.80 Birgunj Sum 246.54 216.51 181.20 172.07 Rasuwa Gadhi - Baireni 82.74 80.20 79.42 74.28 Baireni Baireni - Kathmandu 50.81 40.50 40.66 36.77 and Kathmandu Kathmandu - Birgunj 245.89 111.55 108.36 103.73 Sum 379.44 232.24 228.43 214.78

287 Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography, Vol. 35, No. 4, 281-290, 2017 to choose an optimal route, a detailed economic evaluation Spatial Information Sciences, Vol. XLI-B6, pp. 201-203. of infrastructures that exist and are going to be built in Acharya, T.D., Yang, I.T., Lee, D.H., and Yoo, K.W. the project are very necessary. Due to the lack in available (2017), GIS-based railway route selection: a case study data in Nepal, this study has limitation of not including the of Kathmandu-Birgunj electric railway line, The 19th economic value. To overcome such limitations, government International Conference of Geospatial Information must focus on the development and update of high resolution Sciences and Urban Planning (GISUP 2017, International), geospatial and infrastructure data in Nepal. Only then the GISUP, International, 16-17 February, Nagasaki, Japan, increased utility of these data will ensure the acceleration of pp. 146-149. the development works. Collischonn, W. and Pilar, J.V. (2000), A direction dependent least-cost-path algorithm for roads and canals, 6. Conclusions International Journal of Geographical Information Science, Vol. 14, No. 4, pp. 397-406. Railway transportation has become a necessity for Nepal Douglas, D.H. (1994), Least-cost path in GIS using an due to its growing population and import of daily goods. accumulated cost surface and slopelines, Cartographica: With the interest of Nepalese and Chinese government, a the international journal for Geographic Information and railway connecting China to India has been proposed linking Geovisualization, Vol. 31, No. 3, pp. 37-51. Rasuwa Gadhi to Birgunj in Nepal. In this study, we used Effat, H.A. and Hassan, O.A. (2013), Designing and GIS based LCP analysis and explored various optimal routes evaluation of three alternatives highway routes using that could link the two customs ports. Slope and Land cover the analytical hierarchy process and the least-cost path were used as the main data and their weighted cases were analysis, application in Sinai Peninsula, Egypt, The used as cost raster. Among various cases, routes passing Egyptian Journal of Remote Sensing and Space Science, through both Baireni and Kathmandu were the shortest in Vol. 16, No. 2, pp. 141-151. case D i.e. reclassified slope, land cover and distance to river Farkas, A. (2009), Route/site selection of urban and ridges. This study shows that freely available dataset can transportation facilities: an integrated GIS/MCDM be used for preliminary route planning and can be useful approach, Proceedings-7th International Conference in early planning stages. Yet, there are limitations for more on Management, Enterprise and Benchmarking (MEB detailed economy based optimal routing studies including 2009), Óbuda University, Keleti Faculty of Business and construction cost, bridges and tunnels etc. To overcome these, Management, pp. 169-184. there is a dire need of high resolution updated geospatial data Humagain, M. and Giri, A. (2016), Two Chinese companies for Nepal. keen to build rail network in Nepal, http://kathmandupost. ekantipur.com/news/2016-07-02/two-chinese-companies- Acknowledgment keen-to-build-rail-network-in-nepal.html (last date accessed: 20 August 2017). This study was supported by 2016 Research Grant from Jia, C. and Liqiang, H. (2016), Himalayan rail route endorsed, Kangwon National University (No. 520160528). http://www.chinadaily.com.cn/business/2016-08/05/ content_26350823.htm (last date accessed: 15 August References 2017). NASA JPL (2013), NASA Shuttle Radar Topography Mission Acharya, T.D., Mainali, S.C., Yang, I.T., and Lee, D.H. Global 1 arc second number [Data set], NASA LP DAAC, (2016), Analysis of Jure landslide dam, Sindhupalchowk South Dakota, https://doi.org/10.5067/measures/srtm/ using GIS and remote sensing, ISPRS - International srtmgl1n.003 (last date accessed: 19 August 2017). Archives of the Photogrammetry, Remote Sensing and Slater, J.A., Garvey, G., Johnston, C., Haase, J., Heady,

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